Beijing: China has reportedly built a 22-metre high wall around its navy base in the northeastern Liaoning province to protect the installation from being spied on from nearby "European-style" buildings.

Built at a cost of USD 1.61 million by the People's Liberation Army Navy, the 800-meter-long, 22-meter-high wall was erected around the naval base in Dalian city to keep it safe from being spied on, state-run China News Service said on Sunday.

The wall was erected because a group of European-style villas situated nearby were too tall, it said.

China's military facilities including naval base and airports are threatened by violations of height restrictions by nearby buildings.

More than ten military airports have been relocated or closed due to safety concerns, according to a statement by the General Staff Headquarters of the PLA.

Set up in 1931, Hangzhou Jianqiao Airport is known as the "cradle of China's air forces," yet more than 20 high-rise buildings in the vicinity have exceeded height limits.

Due to local governments' poor balancing of economic development and national defense, high-rise buildings pose threats to military reserve zones in many areas, the report said.

A revised law forbidding buildings and structures from violating clearance limits in reserve zones went into effect on August 1 last year.